In modern cellular networks, Internet Protocol (IP) addressing is being used more extensively than ever before. Mobile devices are equipped with not only cellular transceivers but also data MODEMs such as General Packet Radio Service (GPRS) transceivers, Wi-Fi transceivers, etc. Further, additional network elements such as those that are part of an IP Multimedia System (IMS) use IP addressing to transmit data packets across network elements.
However, these network elements are not being used to the fullest potential. A UMTS Terrestrial Radio Access Network (UTRAN) includes, inter alia, a plurality of access points such as Node Bs (equivalent to GSM Base Transceiver Stations) that are controlled by a controller such as a Radio Network Controller (RNC). The RNC interfaces with other network elements such as a Mobile Switching Center (MSC), and gateways enabling communication with IP networks, such as G-GSN and S-GSN. The problem arises when a mobile device moves from one area serviced by one access point/Node B to another area served by another access point. A seamless handover from one radio to another requires an uninterrupted flow of data to and from the mobile device. Today, seamless handovers require tremendous network resources, and under heavy use, data packets can be lost and connections dropped because existing RNCs are not equipped to re-route data packets as they are performing handovers. Although MSCs perform handover duties, MSCs are not directly involved with base stations/Node Bs, and the precise updated network location of the mobile device is not known to all the intermediary elements. Consequently, data from a source network element is routed across several additional elements before it ever reaches the mobile device.
The problem is compounded by the addition of access points in the form of Wireless Local Area Network (WLAN) hotspots. Since modern mobile devices are able to communicate with different types of networks, additional processing is required to bring awareness of the new location to the network elements routing the data. At present, there is no efficient method for the core network elements to be made aware of the location of the mobile device such that data is transferred effectively to the mobile device via the new access point.
Therefore, what is needed is a device, system, or method to seamlessly route data packets to mobile devices that traverse multiple access points.
The present invention solves the above problems by enabling a controller, such as a RNC or BSC, to map the locations of mobile devices that are connected to various access points on one or more networks. The access points include base stations, Node Bs, wireless LAN, etc., and incorporate or are coupled to network agents. The network agent reports the location of the mobile device to the controller via a plurality of means such as over an IP network, a powerline network, or a satellite network. Using the database, or IP mapping table, having the most current locations of all the mobile devices under its domain or area, the controller can route data packets to the mobile devices using the most effective routing paths.
In one exemplary embodiment, the present invention is a controller for routing a data packet to a mobile device on a network, including a processor, a memory in communication with the processor, the memory including a database containing an Internet Protocol (IP) address associated with a corresponding mobile device, a transceiver in communication with the processor, and routing logic on the memory for receiving a network location from a network agent in communication with the mobile device, updating the database with the network location, and routing a data packet to the mobile device via the network location. The controller may be a radio network controller (RNC) or a Base Station Controller (BSC). The network agent is coupled to an access point enabling the mobile device to access the network. The access point is any one of a Wireless Local Area Network (WLAN) router and a Node B. The controller further performs handovers between the WLAN router and the Node B, or between several WLAN routers or Node Bs. The network agent transmits the network location to the controller via a powerline or satellite network.
In another exemplary embodiment, the present invention is a system for routing a data packet to a mobile device on a network, including a radio network controller, a plurality of access points in communication with the radio network controller, the plurality of access points including at least a Node B and a Wireless Local Area Network (WLAN) router, a network agent coupled to each of the plurality of access points, and a mobile device in communication with one of the plurality of access points, wherein the radio network controller includes a database of network locations for the mobile device, the database including an Internet Protocol (IP) address of the mobile device, a unique identifier of the mobile device, and a network address of access point in communication with the mobile device, the network address being provided to the radio network controller from the network agent, and wherein the radio network controller comprises routing logic to update the database with the network address received from the network agent and route an incoming data packet to the mobile device based on the network address of the access point in communication with the mobile device. The system further includes a Serving GPRS Support Node (SGSN) in communication with the RNC, wherein the network location is transmitted to the RNC via the SGSN.
In yet another exemplary embodiment, the present invention is a method for routing a data packet to a mobile device on a network, including storing an Internet Protocol (IP) address and location information for a mobile device on the network, receiving a network location from a network agent in communication with the mobile device, the network agent being co-located with an access point providing a network access to the mobile device, updating the stored location information for the mobile device with the network location of the access point, receiving a request to transfer a data packet to the mobile device, and routing the data packet to the mobile device via the updated location information. The routing further comprises forwarding the network location of the access point to a source of the request to transfer the data packet.